Process of hardening and waterproofing animal skins.



KARL HARTMANN, 0F BERLIN, GERMANY.

PROCESS OF HARDENING AND WATERPROOFING ANIMAL SKINS.

No Drawing.

Specification of Letters Patent.

Patented Feb. 6, 1912.

Application filed August 5, 1911. Serial No. 642,460.

To all whom it may concern:

Be it known that I, KARL HARTMANN, a citizen of the German Empire, and resident of 111 Lindenstrasse, Berlin, S. W., in the Kingdom of Prussia and in the German Empire, have invented certain new and useful Improvements in the Process of Hardening and Waterproofing Animal Skins, of which the following is a specification.

For waterproofing and strengthening leather it has been proposed to use treatment of impregnation with celluloid solution; also the treatment of soaking the raw skin in a hygroscopic liquid (glycerin), then in oil, and then applying rubber solution.

The present invention consists in a combination of steps which, though not all individually new, produce, when thus combined, an improved result in regard to hardening and waterproofing, and furnish a substitute for leather having an appearance resembling that of horn, and also partaking of some of the advantageous qualities thereof. Skin thus treated, combining great strength with elasticity, is not only highly suitable for the construction of boxes, trunks, boats, military equipments and the like, but also furnishes a substitute for whalebone and horn. It is also a good electrical insulator.

According to the present invention the skin, freed by known methods from hair and flesh, is hardened in a bath containing amyl acetate and acetone (suitable proportions bemg about two parts of the former and one of the latter), the skin being left in this bath for about 48 hours. The skin is then coated with a solution of celluloid in acetone and amyl acetate (suitable proportions being obtained by using approximately" equal parts of these three substances). The solution may be applied with a brush. For protecting the celluloid coating, so as to render same insoluble, the skin is then placed, say for 24 hours, in an alcoholic solution of shellac (say two parts of white shellac in one part of 90% alcohol).

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is The process of hardening and Waterproofing animal skins, after removal of hair and flesh, by treating same in a bath of amyl acetate and acetone, then applying to the skin a solution of celluloid in amyl acetate and acetone, and then treating same in an alcoholic solution of shellac.

In testimony whereof I aifix my signature in presence of two witnesses.

KARL HARTMANN.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of ZPatents, Washington, I). G. 

